The present invention relates to bacterial and microbial contamination of food items. More particularly, the present invention relates to a system and method for identifying contaminated food products, tracing the contaminated food products within the food distribution chain, and facilitating actions such as recalling contaminated food items and alerting consumers through various media.
For the purpose of this invention, the term “pollutants” refers to toxins, harmful bacteria (such as e-coli, Coxiella burnetti, botulinum, thermosaccharolyticum, and the like), pathogens, contaminants, organic agents, inorganic agents, radiological agents, radiological agents or any other non-beneficial agents that find their way into food products. The term “harmful” is used herein means deleterious to human health. Such pollutants may be naturally occurring, maybe the result of a contamination event (such as introduction of the food product into a non-sterile environment), or may be the result of tampering with the food products (as when someone tampered with Tylenol brand of acetaminophen capsules in 1982).
Generally, much of the fresh food supply in the United States and around the world is perishable because of its moderate to high water content and because of its nutritious nature. The causes of deterioration in spoilage of food products include the growth of microorganisms (by far the most common cause), contamination (filth, absorption of odors, etc.), normal respiration (plant tissues), loss of water (sprouting), autolysis (especially fish), various chemical reactions such as oxidation, physiological disorders (such as scald of apples, cold shortening of muscle, chilling injury and anaerobic respiration of plant tissues), and mechanical damage (bruising, and the like).
Spoilage of perishable foods can be prevented only by prompt consumption, which often is not possible, or by prompt effective preservation. Effective preservation not only retards spoilage, but also helps reduce the possibility of contamination of the food product. The aim of commercial food preservation is to prevent undesirable changes in the wholesomeness, nutritive value, or sensory quality of food by economical methods which control growth of microorganisms, reduce chemical, physical, and physiological changes of an undesired nature, and obviate contamination.
Currently, preservation of food can be accomplished by chemical, biological, or physical means. Generally chemical preservation involves the addition to food of such substances as sugars, salts, or acids or exposure of food to chemicals such as smoke or fumigants. Biological preservation involves alcoholic or acidic fermentations. Physical approaches to preserving food include temporary increases in the products energy level (heating or irradiation), controlled reduction of the products temperature (chilling, freezing, and the like), controlled reduction in the products water content (concentration, air dehydration, freeze drying), and the use of productive packaging.
During preservation of moderately or highly perishable foods, the greatest concern is related to microorganisms. Physical methods of preservation result either in death of microorganisms (by temporarily increasing the energy level of a food which is suitably packaged to avoid recontamination), or suppression of their growth (by maintaining the food at sub-ambient temperatures or by removing water followed by packaging to avoid reabsorption of water).
Although certain physical methods of food preservation completely stop growth of microorganisms and greatly retard the rates of chemical reactions (and spoilage), it is important to recognize that none of these methods can completely prevent chemical and physical changes. For example, in frozen foods stored at a recommended temperature of −18 degrees Celsius, microorganisms cannot grow, but degradation of vitamin C, insolubilization of protein, oxidation of lipids, and recrystallization can occur at significant rates. Additionally, methods of preservation that successfully stop the growth of microorganisms sometimes have undesirable consequences with respect to the sensory and nutritional attributes of food. For example, thermal sterilization softens food tissues, degrades chlorophyls and anthocyanins alters flavors, and results in loss or degradation of vitamins.
One method of preservation of food products is called pasteurization. Pasteurization is a heat treatment that kills part but not all of the vegetable microorganisms present in the food, and consequently it is used for foods which are to be further handled and stored under conditions which minimize microbial growth. In many cases, the primary objective of pasteurization is to kill pathogenic microorganisms. Some vegetative spoilage organisms can survive this heat treatment, and thus more severe preservation methods are needed if microbial spoilage is to be prevented. In other cases, such as in beer, pasteurization serves primarily to kill vegetative spoilage organisms. Other preservation techniques used in conjunction with pasteurization typically include refrigeration, chemical additives, packaging, and fermentation.
Pasteurization generally involves heating the food product to a specific temperature for a period of time. The time temperature treatment used in pasteurization depends upon the heat resistance of the particular vegetative or pathogenic microorganism that the process is designed to destroy, and the sensitivity of the product quality to heat. In milk pasteurization for example, the high temperature and short time method involves a comparatively high temperature for a short period of time (e.g., 161 degrees Fahrenheit for 15 seconds for milk), whereas the low temperature and long time procedure involves relatively low temperatures for longer periods of time (e.g., 145 degrees Fahrenheit for 30 minutes for milk). Optimization of the pasteurization process depends on the relative destruction rate of various microorganisms as compared to quality factors of the food product. For market milk, pasteurization conditions are based on the thermal destruction of coxiella burnetti, the ricketsia organism responsible for Q fever. For high acid fruits such as cherries, the pasteurization process is based on successful destruction of yeast or molds. For fermented beverages such as wine or beer, the pasteurization criteria involves the destruction of wild yeasts.
In milk for example, the low temperature long time pasteurization process is targeted toward a particular organism. However, even with such pasteurization, contamination by other pollutants may occur from time to time. Additionally, storage conditions may contaminate the stored milk or provide an ambient condition for the microorganisms to reconstitute. Consequently, contamination of food products by pollutants occurs from time to time. Typically such occurrences are evidenced by sporadic outbreaks of illness among consumers and by occasional recall efforts. Whether the contamination is caused by E coli in tainted ground beef, by ricin in potatoes, or by various other pollutants on various types of food products, it is desirable to identify food contamination events quickly, and to take steps to contain the spread of the contamination so that the consumer impact is minimized.
Generally, once a food contamination is identified, food producers have few options. The food producers can recall all of the food items, assess the risk of not recalling the contaminated items against the costs associated with the recall effort, publically announce the contamination through media outlets, and destroy remaining produce. Typically, food producers employ one or more of these option for each food contamination event. Wrong decisions not only cost money, but may also cost lives (particularly if a recall effort is not mounted quickly).
Unfortunately, it has been found that public announcements of food contamination events are generally not very effective in reaching consumers. Additionally, since food producers are independent, there is no centralized or nation wide system for handling food contamination events. In fact, at present there is no standard method for addressing food contamination events.
Additionally, before remediating the food contamination event through one of the options described above, it is important that the source of the contamination is accurately identified. A misidentification of source can be very costly to food producers and may allow more time for the contaminated food items to circulate and to be consumed before the correct identification is made. Additionally, due to concerns about competition, food processing companies are reluctant to share information about distributors, harvesters and the like. This makes it very difficulty for public health officials to trace food contamination events to the source. Thus, even when the cause of an illness is properly identified by public health officials, reaching the affected consumers, distributors and other people in the food distribution chain can be extremely difficult.